Radiation Hardened Electronically Erasable Read Only Memory (EEPROM)

The highest density radiation hardened non-volatile (NV) memory currently available is a 256 kbit EEPROM based on SONOS technology. One of the major limitations in developing rad hard NV memory has been the cost involved bringing up the NV technology in adedicated rad hard process facility, especially when weighed against the limited market size. One way to bring radiation hardening to an advanced electronic product on a cost-effective basis is to leverage the built-in radiation hardness of a commercialprocess technology. NV flash EEPROM memory technology is popular in the commercial marketplace, with densities up to 256 Mbit in production. Unfortunately, flash EEPROM memory is not available, at any density, in total dose rad hard versions. And, mostcommercial flash EEPROM memories are so soft that impractical amounts of shielding are required to survive even moderate radiation environments. This effort will be an important step in developing rad hard flash EEPROM technology at a commercial fab. Radhard flash EEPROM technology will be a near-term solution to the problem of high density NV memory for space application. It will enable the development of rad hard flash EEPROM memories and embedded NV memory for rad hard ASICs.